Sachdeo Amit, Haffajee Anne D, Socransky Sigmund S
Department of Prosthodontics, Tufts University-School of Dental Medicine, Boston, MA 02111, USA.
J Prosthodont. 2008 Jul;17(5):348-56. doi: 10.1111/j.1532-849X.2008.00301.x.
The oral cavity presents numerous surfaces for microbial colonization. These surfaces produce biofilms of differing complexities unique to each individual. Several studies have looked at biofilms in dentate patients. There has been limited research regarding biofilms on dentures or soft tissues of edentulous patients. The purpose of the present investigation was to provide meaningful data describing microbial ecological relationships in the oral cavity of edentulous patients and to evaluate the microbiota on hard and soft tissue surfaces and saliva in edentulous patients wearing complete dentures.
Sixty-one edentulous subjects with complete maxillary and mandibular dentures were recruited. "Supragingival" biofilm samples were taken from 28 denture teeth for each subject. Biofilm samples were also taken from the dorsal, lateral, and ventral surfaces of the tongue, floor of mouth, buccal mucosa, hard palate, vestibule/lip, "attached gingiva," and saliva. Samples were individually analyzed for their content of 41 bacterial species using checkerboard DNA-DNA hybridization. Levels and proportions of each species were determined for every sample location.
Periodontal pathogens such as Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were clearly present in the samples from the edentulous subjects. Microbial profiles in samples from the soft tissue surfaces differed among site locations. Samples from the dorsum of the tongue exhibited the highest bacterial counts followed by the "attached gingiva" and the lateral surfaces of the tongue, while the lowest mean counts were found in samples from the buccal mucosa and labial vestibules. Using cluster analysis of the proportions of the test species, three clusters were formed. The first cluster comprised saliva, supragingival plaque, and the lateral and dorsal surfaces of the tongue. The second cluster comprised the other six soft tissue surfaces. Species on the denture palate formed a third cluster.
One of the major findings in this study was the detection of periodontal pathogens, A. actinomycetemcomitans and P. gingivalis, in the edentulous subjects, as these species were thought to disappear after removal of all natural teeth. This finding has implications regarding future dental treatment and the general health of individuals. Distinct patterns of microbial colonization were seen on the different soft tissue surfaces. Thus, this investigation provided the first step in defining the organisms that are associated with edentulous patients on both soft (mucosa) and hard surfaces (denture). The study also provided meaningful data that described microbial ecological relationships in the oral cavity of edentulous subjects. The authors believe that this study is the first comprehensive assessment of the microbiota in the complete denture-wearing subject.
口腔为微生物定殖提供了众多表面。这些表面会形成因人而异、复杂度各异的生物膜。多项研究着眼于有牙患者的生物膜。关于无牙患者假牙或软组织上生物膜的研究有限。本研究的目的是提供有意义的数据，描述无牙患者口腔中的微生物生态关系，并评估佩戴全口假牙的无牙患者硬组织和软组织表面以及唾液中的微生物群。
招募了61名佩戴上颌和下颌全口假牙的无牙受试者。从每位受试者的28颗假牙牙齿上采集“龈上”生物膜样本。还从舌背、舌侧和腹侧表面、口腔底部、颊黏膜、硬腭、前庭/唇部、“附着龈”以及唾液中采集生物膜样本。使用棋盘式DNA-DNA杂交技术对样本中41种细菌的含量进行单独分析。确定每个样本位置每种细菌的水平和比例。
在无牙受试者的样本中明显存在诸如伴放线聚集杆菌和牙龈卟啉单胞菌等牙周病原体。软组织表面样本中的微生物谱因部位不同而有所差异。舌背样本的细菌计数最高，其次是“附着龈”和舌侧表面，而颊黏膜和唇前庭样本的平均计数最低。通过对受试菌种比例进行聚类分析，形成了三个聚类。第一类包括唾液、龈上菌斑以及舌的外侧和背侧表面。第二类包括其他六个软组织表面。假牙腭部的菌种形成第三类。
本研究的主要发现之一是在无牙受试者中检测到牙周病原体——伴放线聚集杆菌和牙龈卟啉单胞菌，因为这些菌种被认为在拔除所有天然牙后会消失。这一发现对未来的牙科治疗和个体的总体健康具有重要意义。在不同的软组织表面观察到了不同的微生物定殖模式。因此，本研究为确定在软组织（黏膜）和硬表面（假牙）上与无牙患者相关的微生物迈出了第一步。该研究还提供了有意义的数据，描述了无牙受试者口腔中的微生物生态关系。作者认为这项研究是对佩戴全口假牙受试者微生物群的首次全面评估。
